Problem: $\dfrac{7}{5} - \dfrac{4}{12} = {?}$
Answer: $ = {\dfrac{7 \times 12}{5 \times 12}} - {\dfrac{4 \times 5}{12 \times 5}} $ $ = {\dfrac{84}{60}} - {\dfrac{20}{60}} $ $ = \dfrac{{84} - {20}}{60} $ $ = \dfrac{64}{60}$